我正在学习使用kafka(使用scala API)进行Spark流式传输,并且我正在尝试开发一个简单的应用程序以将kafka应用程序绑定到流式应用程序。使用sbt进行编译是可以的,但是当我进行火花提交时,我总是会遇到相同的错误:java.lang.NoClassDefFoundError。
我安装的Spark版本是2.3.0。
我的build.sbt文件是:
name := "Linking"
mainClass := Some("Main")
scalaVersion := "2.11.8"
libraryDependencies += "org.apache.spark" %% "spark-core" % "2.3.0" % "provided"
libraryDependencies += "org.apache.spark" %% "spark-streaming" % "2.3.0" % "provided"
libraryDependencies += "org.apache.spark" % "spark-streaming-kafka-0-10_2.11" % "2.2.0"
,主要的源文件是:
import org.apache.spark._
import org.apache.spark.streaming._
import org.apache.kafka.clients.consumer.ConsumerRecord
import org.apache.kafka.common.serialization.StringDeserializer
import org.apache.spark.streaming.kafka010._
import org.apache.spark.streaming.kafka010.LocationStrategies.PreferConsistent
import org.apache.spark.streaming.kafka010.ConsumerStrategies.Subscribe
object KafkaStreaming {
def main(args: Array[String]): Unit = {
println("Hello, world!")
val conf = new SparkConf().setMaster("local[2]").setAppName("NetworkWordCount")
val ssc = new StreamingContext(conf, Seconds(1))
val kafkaParams = Map[String, Object](
"bootstrap.servers" -> "localhost:9092,anotherhost:9092",
"key.deserializer" -> classOf[StringDeserializer],
"value.deserializer" -> classOf[StringDeserializer],
"group.id" -> "use_a_separate_group_id_for_each_stream",
"auto.offset.reset" -> "latest",
"enable.auto.commit" -> (false: java.lang.Boolean)
)
val topics = Array("topicA", "topicB")
val stream = KafkaUtils.createDirectStream[String, String](
ssc,
PreferConsistent,
Subscribe[String, String](topics, kafkaParams)
)
stream.map(record => (record.key, record.value))
}
}
我进行了研究,得到了两种解决方案。库版本有问题,并且在spark-submit中包含--jars spark-streaming-kafka-0-10-assembly,但它们都不起作用。
预先感谢